Mine fuze

ABSTRACT

3. A land mine including an electrical detonator, first and second fuzes adapted to be buried in the ground; each fuze comprising a housing, a pressure plate carried by and forming a closure for said housing, an induction coil fixed in said housing, a permanent magnet extending through said coil, said permanent magnet being connected to said pressure plate so as to move in said coil in response to operation of the pressure plate, and a switch having a pair of contacts, one contact being carried by said housing and the other contact being carried by said permanent magnet whereby said switch is closed in response to depression of said pressure plate, said induction coil and said switch being electrically connected in series; opposite sides of said induction coil of said first fuze being connected, respectively, to one side of said detonator and to said switch of said second fuze and opposite sides of said induction coil of said second fuze being connected, respectively to the other side of said detonator and said switch of said first fuze.

[451 Oct. 29, 1974 MINE FUZE [75] Inventors: Joseph P. Rogers, Jr.;Richard G.

Thresher, both of Ledgewood, NJ.

[73] Assignee: The United States of America as represented by theSecretary of the Army, Washington, DC.

[22] Filed: Apr. 13, 1960 [21] Appl. No; 22,066

[52] US. Cl. 102/8, 102/70.2 R [51] Int. Cl. F42b 23/00 [58] Field ofSearch 102/702, 70 G, 70 GI,

[56] References Cited UNITED STATES PATENTS 2,192,542 3/1940 Benedetti[OZ/70.2

2,456,657 12/1948 Vagts 102/8 2,569,808 10/1951 Ensign 102/8 2,703,5303/1955 McGee 102/70.2

Primary Examiner-Samuel W. Engle Attorney, Agent, or FirmEdward J.Kelly; Herbert T. Berl EXEMPLARY CLAIM 3. A land mine including anelectrical detonator, first and second f uz es adapted to be buried inthe ground; each fuze comprising a housing, a pressure plate carried byand forming a closure for said housing, an induction coil fixed in saidhousing, a permanent magnet extending through said coil, said permanentmagnet being connected to said pressure plate so as to move in said coilin response to operation of the pressure plate, and a switch having apair of contacts, one contact being carried by said housing and theother contact being carried by said permanent magnet whereby said switchis closed in response to depression of said pressure plate, saidinduction coil and said switch being electrically connected in series;opposite sides of said induction coil of said first fuze beingconnected, respectively, to one side of said detonator and to saidswitch of said second fuze and opposite sides of said induction coil ofsaid second fuze being connected, respectively to the other side of saiddetonator and said switch of said first fuze.

3 Claims, 2 Drawing Figures MINE FUZE This invention relates to landmines and more particularly to antitank land mines which will bedetonated only after a substantial portion of the tank has passedthereover.

In the use of land mines as an anti-tank weapon the most destructiveeffect on a tank cannot be obtained if the mine is detonated when firstcontacted by the tank. Detonation to be most effective should occurdirectly under the tank which is its most vulnerable point. Time delaysbetween fuze actuation and detonation have not proven entirelysatisfactory.

Briefly, our invention comprises a land mine having a pair of spacedfuzes which must both be operated before detonation will occur. Further,the second fuze must be operated while the operating means, i.e. tank,is still in contact with the first fuze. Thus, it will be sen that byproperly spacing the fuzes and correctly positioning the mine withrespect thereto the mine can be made to explode directly beneath a tankat its most vulnerable point. Further, since the tank must be in contactwith both fuzes at the same time the mine cannot be detonated by thesequential operation of the fuzes by personnel or the like.

An object of the invention is to provide a land mine which will explodedirectly underneath a tank.

Another object of the invention is to provide a land mine with spacedfuzes, both of which must be operated before the mine will be detonated.

A further object of the invention is to provide a land mine havingspaced fuzes which must be contacted at the same time in order todetonate the mine.

Another object is to provide a land mine having an electrical detonatorand in which actuating current is induced upon operation of the fuze bya tank.

Yet another object of the invention is to provide a mine having anelectrical detonator and a pair of fuzes each having an induction powersource and switch in circuit with the detonator.

A further object is to provide a mine fuze having an induction powersource and switch which are simultaneously operated by contact with atank or the like.

These and other objects will become more apparent when reference is hadto the following detailed description and accompanying drawing in which:

FIG. 1 is a sectional view of one of the fuzes of my invention showingthe induced current power source and switch, and

FIG. 2 is a schematic diagram showing the two fuzes and the manner inwhich they are connected to the mine detonator.

The land mine of the present invention utilizes two fuzes, one of whichis shown in detail in FIG. 1. Each fuze constitutes an electrical powersource for the mine detonator and includes an induction power source andswitch.

As shown in FIG. 1, the fuze is indicated in its entirety by referencecharacter 1 and includes the housing 2 which is adapted to be buried inthe ground. The housing is cup shaped as shown and is provided in itsbottom wall with annular channel 3 and the two upstanding webs 4.Supported by and connected across the tops of the webs 4 is the magnetsupport bar 5 which carries the pivot pin 6. Pivotally mounted on thepin 6 is the yoke 7 which carries the pin 14 andmagnet support wires 9.Connected between the magnet support wires 9 is the permanent magnet 10.

Slidably mounted on the housing 2 is the pressure plate 11 which has theannular flange 12 to slidably engage the housing. The pressure platecarries the pivot 13 which is provided with the opening 14 to looselyreceive the pin 14. The head 15 on the pin 14 prevents withdrawal of thepin from the pivot 13. The resetting spring 16 is received in the groove3 and acts to urge the pressure plate 11 upward.

Mounted within the housing 2 by means of the mounting pads 17 is thecoil 18 which surrounds the magnet 10. The bottom wall of the housing isprovided with an aperture which threadedly receives the adaptor l9 andinsulating gasket 20. One lead wire 21 from the coil is led directlythrough the gasket 20. The pivoted yoke 7 carries one contact 22 of aswitch, and the second coil lead 23 is led from the coil to the switchcontact 22 and then out through the gasket 20. The second switch contact24 is fixed to the web 4 and has lead wire 25 connected thereto. Thelead 25 is conducted from the switch contact out of the housing throughgasket 20.

The operation of each individual fuze should now be apparent. Whenpressure is applied to the pressure plate 11, the plate is depressedagainst the action of the spring 16. This pivots the yoke 7 and thepermanent magnet 10 carried thereby. The lines of flux of the magnetthen cut the turns of the coil 18 and induce a current therein and hencein leads 21 and 23. At the same time, the switch contacts 22 and 24 areclosed connecting the leads 23 and 25.

The schematic diagram of FIG. 2 illustrates the manner in which a pairof fuzes similar to the one shown in FIG. 1, may be used with a singlemine so that both fuzes must be operated to cause detonation. Theelectrically operated detonator of the mine is indicated at 26. The fuzeunits are indicated as fuze No. l and fuze No. 2. One side of inductionpower source 27 of fuze No. l is connected to the detonator 26 and oneside of induction power source 28 of fuze No. 2 is also connected to thedetonator 26. The opposite side of induction power source 27 isconnected to switch contact 24 of fuze No. 2 while the opposite side ofinduction power source 28 is connected to switch contact 22 of fuze No.I. In the operation of a mine with two fuzes, let it be assumed that atank first operates fuze No. 1, causing power to be generated by powersource 27 and closing switch contacts 22 and 24. Switch contacts 22 and24 of fuze No. 2 are still open, however, and the detonator 26 is thusnot in circuit, and the mine does not explode. The electrical pulsegenerated by source 27 is not stored and dissipates. If now the tankproceeds and operates fuze No. 2 while still being in contact with fuzeNo. 1 so that switch contacts 22 and 24 on fuze No. 1 remain closed,power is induced in power source 28 and switch contacts 22 and 24 offuze No. 2 are closed. Inasmuch as switch contacts 22 and 24 of fuze No.1 are also closed and no further current is being generated by source27, the detonator is in circuit and the mine is exploded. It will benoted, however, that if the pressure of the tank is removed from fuzeNo. 1 allowing switch contacts 22 and 24 of fuze No. 1 to open beforefuze No. 2 is actuated, the mine will not detonate upon actuation offuze No. 2. Obviously the mine would also be detonated by a reverseoperation, i.e., ac-

tuation of fuze No. 2 and then actuation of fuze No. 1 while the switchof fuze No. 2 is still closed.

it will thus be seen that a mine having two fuzes connected as shown inFIG. 2 will be effective to explode only after a substantial part of thetank has passed thereover depending on the spacing of the fuzes. Theapplication and release of a load to one fuze before the application ofa load to the second fuze will not detonate the mine.

While we have shown in FIG. 2 the use of two fuzes with a mine, it willbe apparent that one fuze could be assembled to a mine with theinduction power source and switch in series with the detonator toprovide a contact mine fuze. Depending on the strength of the returnspring, the mine could then be used for anti-tank, anti-personnel orgeneral purposes.

it will be apparent that the embodiment shown is only exemplary and thatvarious modifications can be made in construction and arrangement withinthe scope of the invention as defined by the appended claims.

We claim:

1. In a land mine, an electrical detonator, first and second fuzesadapted to be buried in the ground and operated by external pressure,each fuze comprising an electrical power source and a switch connectedin series, one side of the power source of the first fuze beingconnected to said detonator and the other side of said power sourcebeing connected to the switch of said second fuze, one side of the powersource of said second fuze being connected to said detonator and theother side of said last named power source being connected to the switchof said first fuze whereby said detonator will not operate unless bothsaid switches are closed.

2. In a fuze for a land mine adapted to be buried in the ground asdefined in claim 1, each said electrical power source being of theinduction type and generating power in response to operation of saidfuzes whereby both of said switches must be closed one at a time tocause detonation.

3. A land mine including an electrical detonator, first and second fuzesadapted to be buried in the ground; each fuze comprising a housing, apressure plate carried by and forming a closure for said housing, aninduction coil fixed in said housing, a permanent magnet extendingthrough said coil, said permanent magnet being connected to saidpressure plate so as to move in said coil in response to operation ofthe pressure plate, and a switch having a pair of contacts, one contactbeing carried by said housing and the other contact being carried bysaid permanent magnet whereby said switch is closed in response todepression of said pres- 'sure plate, said induction coil and saidswitch being electrically connected in series; opposite sides of saidinduction coil of said first fuze being connected, respectively, to oneside of said detonator and to said switch of said second fuze andopposite sides of said induction coil of said second fuze beingconnected, respectively to the other side of said detonator and saidswitch of said first fuze.

1. In a land mine, an electrical detonator, first and second fuzesadapted to be buried in the ground and operated by external pressure,each fuze comprising an electrical power source and a switch connectedin series, one side of the power source of the first fuze beingconnected to said detonator and the other side of said power sourcebeing connected to the switch of said second fuze, one side of the powersource of said second fuze being connected to said detonator and theother side of said last named power source being connected to the switchof said first fuze whereby said detonator will not operate unless bothsaid switches are closed.
 1. In a land mine, an electrical detonator,first and second fuzes adapted to be buried in the ground and operatedby external pressure, each fuze comprising an electrical power sourceand a switch connected in series, one side of the power source of thefirst fuze being connected to said detonator and the other side of saidpower source being connected to the switch of said second fuze, one sideof the power source of said second fuze being connected to saiddetonator and the other side of said last named power source beingconnected to the switch of said first fuze whereby said detonator willnot operate unless both said switches are closed.
 2. In a fuze for aland mine adapted to be buried in the ground as defined in claim 1, eachsaid electrical power source being of the induction type and generatingpower in response to operation of said fuzes whereby both of saidswitches must be closed one at a time to cause detonation.